Lighting filament



FIG. 1 is a perspective view of a lighting filament showing the new design;

FIG. 2 is a front elevation view of the lighting filament of FIG. 1;

FIG. 3 is a rear elevation view of the lighting filament of FIG. 1;

FIG. 4 is a left side elevation view of the lighting filament of FIG. 1;

FIG. 5 is a right side elevation view of the lighting filament of FIG. 1;

FIG. 6 is a top plan view of the lighting filament of FIG. 1; and,

FIG. 7 is a bottom plan view of the lighting filament of FIG. 1.

The broken lines immediately adjacent shaded areas represent bounds of the claimed design, while all other broken lines are directed to environmental features or portions of the lighting filament that form no part of the claimed design. None of the illustrated broken lines form any part of the claimed design. 

CLAIM I claim the ornamental design for a lighting filament, as shown and described. 